Electric motor.



Patented lune I9, |900.

C. L. BUNDY..

ELECTRIC MOTOR.

(Application filed June 6, 1898.)

(No Model.)

J/l/ e @gil/2% JM diaz# lill/Il l lllIIlIlI-IIIIYIIIIII l/J will/l1UNITED STATES PATENT OFFICE.

CLIFTON L. BUNDY, OE PHILADELPHIA, PENNSYLVANIA.

ELECTRlCMoToR.

SPECIFICATION forming part of Letters Patent No. 651,945, dated d' une 19, 1900. Application filed June 6, 1898. Serial No.` 682,697. (Nomodel.)

To all whom it may concern:

Be it known that I, CLIFTON L. BUNDY, a citizen of the United States,residing at Philadelphia, in the county of Philadelphia and State ofPennsylvania, haveV invented a certain new and useful Improvement inElectric Motors, of which the following is a specification.

My invention relatesto a new and useful improvement in electric motorsand dynamos, and especially to those known as magnetoelectric machines,and has for its object to provide a simple and effect-ive device of thisdescription in which the wire is Wound only upon the armature.

Vith this end in view the invention consists in the details ofconstruction and combination of elements hereinafter set forth and thenspecifically designated by the claim.

The construction and operation will now be described in detail,referring to the accompanying drawings, forming a part of thisspecification, in which- Figure l isa central cross-section of a motormade in accordance with my improvement; Fig. 2, a bottom plan view., andFig. 3 a section showing a modification of the field illustrated in Fig.1.

In carrying out my invention as here embodied I provide a field memberA, which may be of steel, cast-iron, or laminated iron, here shown assolid and bipolar, and this field member has channels B formed thereinadapted to receive and permit the revolving of the armature C therein.The core D of the armature is circular and may be of steel, cast-iron,or laminated iron, with or without teeth, and around this core is woundin proper section the wire E for the energizing of the armature.

A spider F is provided for the support of the armature and is connectedtherewith by the posts G, both the spider and post being of non-magneticmaterial, and this spider is adapted to revolve upon the central spindleI-I by the hub I being journaled thereon, and for convenience inlubricating this bearinga thimble-shaped cup .I is threaded upon thelower end of the spindle, as indicated at K, and extends upward aroundthe hub in such manner as to hold a quantity of oil, which latter isadmitted to the bearing through the hole L. .A commutator M is carriedby the spider, and the brushes N are arranged to bear thereagainst, saidbrushes being supported by the arms O, which are secu red upon thespider. -Any suitable means may be utilized for the transmission ofmotion from the armature tothe Work to be accomplished. The brushes arehere shown as consisting of blocks of carbon or other suitable materialset in the hollow arms O, which act as guides for said brushes, andsprings Oare arranged to bear upon the outer ends of said brushes, so asto force them inward against the commutator. From this description itwill be seen that the electric current transmitted to the wire coils Qwill energize the armature, the magnetic lines of force emanatingtherefrom so acting upon the field member as to bring about a countermagnetic force, which will cause the armature to revolve,thus avoidingthe necessity of Winding the field, and it is to be noted that the eldmember is not a permanent magnet,but depends entirely upon the countermagnetic force developed therein by the magnetism generated in thearmature.

In Fig. 3 I have illustrated a slightly-modified form of the fieldmember, which has an open space R formed in the central portion thereof,thus reducing its weight and avoiding the retention of residuarymagnetism, thereby permitting the changes therein to more rapidly takeplace. Of course any number of poles may be used upon the field member,and it is also obvious that the field may be the revolving member, whilethe armature may remain stationary. This is accomplished by rotating thebrushes wit-h the field member and attaching two collecting-rings forconveying the current to the armature. The magnetic lines of forceemanating from the energized armature-coils act upon the field membersame as before stated. A motor constructed in accordance with myimprovement can be used in connection with either a' direct oralternating current.

a shows an automatic short-circuiting device for carrying the current incase anything should happen to the brushes, thus avoiding the burningout of the armature-Winding. The arm ov is provided with a plate ofnonconducting material o2, against which the curved end of theshort-circ uiting device rests, said plate being of such material and ofsuch ICO thickness as to be penetrated by the current in case thecurrent is abnormal. Under ordinary conditions the circuit Would be fromthe armature to the communication through the Wiring shown and from thecommunication through the brushes, brush-holders, and the Wiresconnected to the brush-holders. In case of abnormal current thenon-conductin g material would fuse, and the short-circuiting arm aWould contact with the brush-holder and the current Would then pass fromone brush to the other.

Other slight modifications might be made in the construction here shownWithout departing from the spirit of m'y invention, and I therefore donot Wish to he limited to these exact details.

Having thus fully described my invention, what I claim as new and usefulis- In an electric motor, a field member having channels, an armature,comprising` a circular core having Wound thereon sections of wire-lyingin the channels of the field member, a spider below the armature, postssecured to the core of the armature and supported by the spider, saidspider having a hub journaled on a central spindle, a commutator carriedby the spider, brush-holding arms, brushes therein bearing against thecommutator, springs secured to the brush-holders and bearing against theouter ends of the brushes, a short-circuiting arm secured to onebrush-holder at one end and having its opposite end bearing against afusible disk on the opposite brush-holder.

In testimony whereof I have hereunto affixed my signature in thepresence of two subscribing Witnesses.

CLIFTON L. BUNDY.

Witnesses:

JOSHUA R. MORGAN, FRANK M. BOLTON, J r.

